It is well understood, that a want of rational employment is a very successful mode of courting delirium; that an indulgence in those reveries which keep the imagination on the wing, and imprison the understanding, is likely to promote it: and it must be owned, that the same effect has often been produced, where vanity or ambition has urged minds, puny by nature, and undrilled in intellectual exercises, to attempt to grasp that which they were unable to embrace. This may be illustrated by the following case. A young gentleman of slender capacity, and very moderate education, at the age of nineteen, was placed in a merchant's counting house, where he continued for two years diligently, though slowly, to perform the duties of the office. Coming at this time into the possession of considerable property, and perhaps, aware of the uncultivated state of his own mind, he very laudably determined to improve it. He frequented the society of persons esteemed learned and eminent in their different professions, and became much delighted with their conversation; but at the same time sensible that he was unable to contribute to the discourse. He resolved to become a severe student, and for this purpose purchased an immense quantity of books on most subjects of literature and science. History commenced the career of his enquiries: Rollin, Gibbon, Hume and Robertson were anxiously and rapidly perused; but he never paused to consider, or to connect dates and circumstances, so that these excellent authors, after he had waded through them, left scarcely an impression on his mind. Chemistry next engaged his attention, and on this subject, he pored over many volumes with little advantage: the terms proved a source of embarrassment, and he made no experiments. In a hasty succession, the ancient languages, antiquities, etymology, agriculture, and moral philosophy, occupied his mind. About eight hours were daily devoted to reading. Somewhat more than two years were consumed in this employment, which had distracted his mind, without conferring any positive knowledge. His friends and acquaintances now began to perceive a considerable alteration in his temper; though naturally diffident, he had assumed a high degree of literary importance, and plumed himself on the extent of his learning. Before this excessive, but ill-directed application, he was a strict relator of the truth, but he now found a convenience in supplying by fancy, that, which the indigence of his memory was unable to afford. Shortly he began to complain that he could not sleep, and that the long night was passed in shifting from side to side. "Lasso, ch'n van te chiamo, et queste oscure, Et gelide ombre in van lusingo: o piume D'asprezza colme: o notti acerbe, et dure." _Gio: Della Casa._